You near the time when you are respected (OR, to be realistic, discarded) as a senior citizen, you tend to worry more about health than anything else. When you were a kid, people would tell you 'Health is Wealth' and you would scoff at it saying, "How do I buy a car with health? Unless I sell my kidney?" NOW...you actually start realizing that, even if health cannot create wealth, ill-health can melt it faster than anything else. And so...
Marundhena vendaavaam yaakkaikku arundhiyadhu atradhu potri unin - Tirukkural
You'll not need any medicine if you eat only after your previous meal is completely digested - Loose translation.
Now, Tiru is a wise man. He certainly does not mean that if you break a bone, all that you need to do is to eat only when you are hungry for the bone to set itself. Nor, I presume, is he really assuming that Covid will not bother you as long as you watch your diet.
They lived in kindlier times. So, what bothered them, primarily, were the so-called lifestyle diseases. And lifestyle diseases were, by and large, a product of bad dietary practices and lack of exercise. So, Tiru has a point when he says that not stuffing your face at all times is a good way to remain healthy.
Ah, now, there you go. "As long as I am hungry when I eat, I'm Ok? No problem with how much I eat?" Well, not really. Tiru probably anticipated that you'd say that, so he followed through in the very next Kural:
Atraal Alavarindhu unga aqdhudambu petran nedidhuykkum aaru - Tirukkural
Once hungry, eating in moderation is the key to the embodied surviving long - Loose Translation.
There you go. No overeating, sorry. "Aha! But I CAN eat ANY food in moderation. Tiru has no problem with junk food." you scream in delight. You ought to know better. When has ANYONE giving dietary advice given pleasing advice? Advice that you can feel happy about?
So, yes, Tiru follows through with this one
Atradhu arindhu kadaipiditthu maaralla thuykka thuvarappasitthu - Tirukkural
Ensuring completion of digestion and when you are truly hungry eat agreeable foods - Loose Translation
And, therein lies the problem. Like your modern doctors, Tiru also is disinclined to think that burgers and french fries, pastries and colas are 'agreeable foods' no matter how agreeable they seem to your tongue. He only means foods that are agreeable to your health.
Leave it...it's too depressing. Why is it that what's enjoyable is so seldom healthy?